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21.
Capturing quality requirements of product family architecture 总被引:1,自引:0,他引:1
Software quality is one of the major issues with software intensive systems. Moreover, quality is a critical success factor in software product families exploiting shared architecture and common components in a set of products. Our contribution is the QRF (Quality Requirements of a software Family) method, which explicitly focuses on how quality requirements have to be defined, represented and transformed to architectural models. The method has been applied to two experiments; one in a laboratory environment and the other in industry. The use of the QRF method is exemplified by the Distribution Service Platform (DiSeP), the laboratory experiment. The lessons learned are also based on our experiences of applying the method in industrial settings. 相似文献
22.
Intra-muscular and inter-muscular variation in carbon turnover of ovine muscles as recorded by stable isotope ratios 总被引:1,自引:0,他引:1
Sabine M. Harrison Frank J. Monahan Aidan P. Moloney Simon D. Kelly Fionnuala Cuffe Jurian Hoogewerff Olaf Schmidt 《Food chemistry》2010
In the case of muscle-based foods, the incorporation of dietary isotopic signals into muscle tissue is a dynamic process and it is not known whether all muscles, or locations within a muscle, have the same isotopic composition. Therefore, an experiment was conducted in which 28 lambs were switched from a control diet to an isotopically distinct experimental diet offered at two different energy allowances (EA). Small, albeit significant, differences were detected in tissue carbon (C) turnover within the muscle Longissimus dorsi. Inter-muscular comparison showed similar C half-lives for four of the five analysed muscles. The results also clearly demonstrated that the EA had a significant impact on intra- and inter-muscular C turnover. The findings of similar tissue C turnover of several muscles sold as meats and the comparable tissue-diet fractionation of the analysed muscles (both within the same EA) will enable scientists to analyse different meat samples according to availability without introducing large biases. However, EA must be considered a factor of uncertainty. 相似文献
23.
Sourdoughs, in which Lactobacillus sanfranciscensis is the predominant bacterial species, are distinctive of some traditional Italian sweet baked products like Panettone. The direct extraction of amplifiable bacterial DNA from products subjected to heat treatment represents a valid tool to identify and trace microbial species originally present in the food matrices. Three types of protocols for the isolation and clean-up of DNA (CTAB, Wizard® DNA Clean-Up System, NucleoSpin® Food) were applied on mother, final dough and end-product samples and compared through the determination of the maximum amplifiable dilution by a PCR reaction targeting two fragments (1460 and 153 bp long) of 16S rDNA region of Lb. sanfranciscensis. CTAB extracting protocol was revealed to be the best for isolating DNA. In dough samples the amplification with the 153 bp fragment showed signals at concentration levels that are comparable with the values obtained from the plate counts, and two log cycles higher than those found with the amplification targeting the 1460 bp fragment. In the cooked samples only the 153 bp amplicon was detected, indicating that oven cooking degrades DNA into small fragments. 相似文献
24.
Indications for the applicability of element signature analysis for the determination of the geographic origin of dried beef and poultry meat 总被引:2,自引:0,他引:2
Bettina M. Franke Max Haldimann Jürg Reimann Beatrice Baumer Gérard Gremaud Ruedi Hadorn Jacques-Olivier Bosset Michael Kreuzer 《European Food Research and Technology》2007,225(3-4):501-509
In order to determine the geographic origin of poultry and dried beef, concentrations of a total of 72 different elements
(occasionally represented with several isotopes) were analyzed by inductively coupled plasma high resolution mass spectrometry
(ICP-HRMS). Additionally, gross chemical composition (GCC) was analyzed. The 25 poultry breast filets samples originated from
Switzerland, France, Germany, Hungary, Brazil, and Thailand, and the 23 dried beef samples, made from M. biceps femoris and M. semitendinosus, were produced in Switzerland, Austria, Australia, United States, and Canada out of raw meat originating either from these
or from other countries. A total of 66 and 46 of the elements and isotopes followed were detected in beef and poultry, respectively.
For statistical analyses, only the most abundant isotopes per element were used. For both poultry meat and dried beef, a differentiation
of the origins was possible using those elements, which were significantly different across countries (As, Na, Rb, and Tl
in poultry; B, Ca, Cd, Cu, Dy, Eu, Ga, Li, Ni, Pd, Rb, Sr, Te, Tl, Tm, V, Yb, and Zn in beef). No sufficient differentiation
between origins was possible with GCC. Further studies have to confirm the suitability of this approach for meat authentication
with more samples. 相似文献
25.
Ananías Pascoal Marta Prado Pilar Calo Alberto Cepeda Jorge Barros-Velázquez 《European Food Research and Technology》2005,220(3-4):444-450
The identification of beef in animal foods is a major concern not only for the prevention of commercial fraud, but also to avoid safety risks deriving from the presence of prohibited bovine material that might be harmful to both human and animal health. Here we report a novel set of bovine-specific primers, CYTbos1 (forward) and CYTbos2 (reverse), which allow the specific amplification of a 115 base pair fragment of the bovine cytochrome b gene (cytb) between nt 844 (mitochondrial site 15,590) and nt 958 (mitochondrial site 15,704), no cross-reaction being observed with DNA from another 12 frequent commercial meat species. The polymerase chain reaction product obtained is cleaved specifically by endonucleases ScaI and TspE1 to achieve further confirmation evidence. The sensitivity of the proposed method was 0.025%. The CYTbos primers successfully detected bovine DNA in meat samples processed for 20 min at 133 °C/300 kPa or for 2 h at 121 °C. CYTbos primers also detected bovine DNA in heat-processed commercial meat products exhibiting a complex nature, as well as in bovine specific risk materials. The proposed polymerase chain reaction method, aimed at detecting a small and specific fragment of the bovine mitochondrial DNA, may be especially useful for the direct identification of bovine DNA in foodstuffs subjected to severe heating under overpressure conditions. 相似文献
26.
27.
In order to face new regulation directives regarding the environment and also for improving their customer relationship, enterprises
have to increasingly be more able to manage their product information during the entire lifecycle. One of the objectives among
others in this paper is to deal with product traceability along the product lifecycle. To meet this objective, the information
system has to be designed and, further built in such a way all information regarding products is recorded. The IEC 62264 standards
define generic logical models for exchanging product and process information between business and manufacturing levels of
enterprise applications. Thus, it can be a base for product information traceability. However, its complexity comes from the
fact it mixes conceptual and implementation details while no methodology exists that defines how to instantiate it. Product
traceability is then needed to increase its abstraction level in order to concentrate on its concepts and managing its application
by providing a methodology for its instantiation. In this paper, we propose to map the IEC 62264 standard models to a particular
view of Zachman framework in order to make the framework concrete as a guideline for applying the standard and for providing
the key players in information systems design with a methodology to use the standard for traceability purposes. 相似文献
28.
评价动态有效位数的述评 总被引:7,自引:0,他引:7
介绍了动态有效位数的含义及溯源性,以及评价动态有效位数的两种方法--正统波拟合法和FFT法,并说明了其各自的优缺点,此外,详细讨论了评价动态有效位置过程中应注意的几个问题:等相位密度采信问题、整周期信号采样问题、拟合收敛性问题、拟合初始值选取问题和校准软件评价问题等。同时给出了两条具有典型代表性的动态有效位数频率特性曲线的实测例证。 相似文献
30.
Julio Garrido Campos Author Vitae Martin Hardwick Author Vitae 《Computer aided design》2006,38(5):540-551
This paper proposes an information model for tracing CNC manufacturing operations. The objective of the model is to assure that traceability data is comprehensive and available for every CNC machined product, independent of the relationship between the subcontractor and the contractor. The prominent feature of the model is a link between CNC report data for a product instance, the CAD design and the CAM data. This link enables users to browse the traceability data and understand the relationships between the manufacturing process, the CAD design and the CAM data. The link is independent of the systems used to build the CAD and CAM data, and allows the users to be sure the manufactured product contains the required characteristics. Then if a product instance fails, this linkage will make possible to analyze the trace data and identify any exceptions or unusual conditions in the manufacturing process. 相似文献